The present invention broadly relates to surgical tables and, more specifically, pertains to a new and improved construction of operating table, particularly for microsurgery of the throat, nose or ears of a patient.
Generally speaking, the operating table of the present development is of the type in which the location of the operating site or field, during surgically required pitching and rolling movements of the patient rest or support structure, essentially remains locally unchanged, and which comprises a rolling or roll axis disposed within a vertical plane which is substantially parallel to the longitudinal direction of the patient rest or support structure.
An operating table of this type is known, for example, from European Pat. No. 0,086,881, published Aug. 31, 1983 and the cognate U.S. Pat. No. 4,558,857, granted Dec. 17, 1985. The supporting frame carrying the patient rest or support structure is supported at the longitudinal axis of the operating table by means of a parallelogram lever linkage arrangement. A drive or drive mechanism accomplishes by means of this parallelogram lever linkage arrangement the rolling motion or movements of the patient rest or support structure about the longitudinal axis of symmetry of the latter. By virtue of the parallelogram lever linkage arrangement or arrangements, the rolling or pivotal movements of the patient rest or support structure are carried out in such a manner that an operating punctiform location in the operating site or field of the patient, which operating punctiform location is essentially disposed within the longitudinal plane of symmetry, will remain unchanged in position. However, this parallelogram lever linkage arrangement is complicated and the manufacture of such constructions requires a corresponding constructional expenditure and is therefore generally uneconomical.
Parallelogram lever linkage arrangements of prior art operating-table constructions constitute a considerable share of the production costs of an operating table, especially since for static reasons such arrangements have to be provided in duplicate or as a pair. The relative large number of moving parts and components also has the disadvantage of a large number of flexible or articulated links or connections, so that a relatively high expenditure is already required for the production of a linkage mechanism which has to be substantially free from play. The total play increases with the working or operating time and, accordingly, the accuracy of motion and the stability decrease. It is readily conceivable what this can mean in the very special field of microsurgery.